"A first chance exception of type 'Microsoft.CSharp.RuntimeBinder.RuntimeBinderException' occurred in Microsoft.CSharp.dll"

"A first chance exception of type 'System.Web.HttpException' occurred in System.Web.dll"
These exceptions are being thrown from core orchard modules. Although their caught, they are so many that I can't help but wonder if they might affect performance. They seem to happen on every request.
There are a lot of InvalidCastExceptions as well where string is being cast to various types like Nullable<int>.